Some few words regarding my PIC of choice…maybe someone is interested in my opinions about these little brains.

eniElectro is officially enrolled soo…on with the show :)

In this related article I am going to talk to you about my PIC and why I chose my PIC to program on. First of all let me begin by saying that, maybe you read my last article, my current PIC is model 16F628A.

What are the main characteristics of it? You might ask…

Let’s wait on a second and try to think what do we point out when talking about a PIC’s characteristics?

Well…first of all, it is an electronic component so, unlike software thingy, it exists in the real world and you can touch it. A PIC is an integrated circuit. That means that it has to have some pins to which other electronic components can connect. The PIC16F628A comes in a 18DIP package which means that it has 18 pins for various purposes.

[PIC PIN layout]

Another thing for which a microcontroller is “famous” for is its internal memory. The internal memory consists of 3types: FLASH memory, in which you write your code to, RAM and EEPROM. RAM memory is, in short memory kept alive by current while EEPROM is a memory where you do not need current to host it. In fact, data written to EEPROM has a lifespan of 40 years, which means that you can write to EEPROM and let your children find out what you have written.

The space available on a 16F628 is as follows:

You may be wondering what does the x14 and the x8 represent? Well…a word [instruction] in a pic is held in its specifically number of bits as its specification states. 16F628 is part of the 16F family, which means that an instruction takes 14bits of memory…so you can ad 2048 instructions to 16F628. X8 represents the same, stating that the data held in RAM and EEPROM are 8bits in length.

We’ve seen the package, its memory, now on with some other interesting capabilities of this PIC:

• It has a total of 35 instructions to be learned [comes from the characteristics of its class]
• Operating speed is at 20 MHz – 200ns/instructions [there are some two-cycle instructions]
• It contains a 8 level hardware stack
• It has the capability of accessing memory directly/indirectly or by relative
• It supports interrupts
• It has 16 I/O ports , most of them bidirectional
• Contains an analog comparator module [thing that I haven’t explored yet]
• It has 3 timers to work with
• It contains an USART [Universal Synchronous/Asynchronous Receiver/Transmitter] very well for radio communication

Ø Has some specific microcontroller features that I will talk about when there will be the case

An interesting thing [or so I thought so] is memory access. Normally, the memory is laid out linear in a computer. In PIC this is not the case. Memory is laid on banks [or memory banks] and in working with memory locations; this must be taken into account before doing anything. 16F628 has its memory scattered along 4 banks, the way you access these banks I will show you in future news.

The reason I said that this PIC is for beginners is because its characteristics… it has only 35 instructions to be learned, it has a good memory and the applications you can do with it are many…well suited for a beginner like myself to enjoy.

I am developing on this PIC for a relative short amount of time and let me say that it is a pleasure working with it… It gives you so many ideas of development that you think that there is no need for a powerful counterpart, all that a beginner – medium developer wants, it can be found on this PIC, this is for sure.

I will continue on working with this microcontroller for I have some plans to develop and it will be at its core…thinking and deciding as I say it to do.

Of course…I will post my developments on the site, so stay tuned ;)

Probably my next news on this category will consist of a short tutorial on how to program these little gadgets, nothing fancy…just to show how easy it is to program them.

Well, that’s enough to be said about MY PIC for now…sure, each and every characteristic can be detailed and will be detailed as soon as the need to be explored will be obvious, till then, take care ;).